Charging circuit, electronic equipment and charging method

Abstract

The invention provides a charging circuit, electronic equipment and a charging method, and relates to the technical field of charging. The charging circuit comprises a boost module which comprises a power output pin and a feedback pin, and the power output pin is used for charging to-be-charged equipment; the feedback pin is used for adjusting the voltage output by the power supply output pin according to the resistance value of the divider resistor connected to the feedback pin; the control module comprises a PWM output port and a voltage acquisition port, and the PWM output port is used for outputting PWM waves with different duty ratios so as to adjust the resistance value of the divider resistor; and the voltage acquisition port is used for acquiring the voltage fed back by the to-be-charged equipment so as to determine the charging state of the to-be-charged equipment. According to the invention, the duty ratio of the PWM wave can be adjusted according to the charging state of the to-be-charged device, so that the voltage output by the power supply output pin can be flexibly adjusted. The charging efficiency of the to-be-charged device can be improved, energy loss is avoided, and meanwhile the heating value of the device in the charging process is reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of charging technologies, and particularly to a charging circuit, an electronic device, and a charging method. Background Art

[0002] In various electronic devices, linear charging is a common charging method to improve the power supply speed of the device.

[0003] In related technologies, charging devices matching various electronic devices usually output a stable and unchangeable constant voltage. However, when linearly charging an electronic device with a charging device having a constant voltage output, it will cause relatively high energy loss, resulting in low charging efficiency of the electronic device and a large amount of heat generation during the charging process. Summary of the Invention

[0004] To overcome the problems existing in the related technologies, the present disclosure provides a charging circuit, an electronic device, and a charging method.

[0005] According to the first aspect of the embodiments of the present disclosure, a charging circuit is provided, including:

[0006] A boost module, including a power output pin and a feedback pin. The power output pin is used to charge a device to be charged; the feedback pin is used to adjust the voltage output by the power output pin according to the resistance value of a voltage-dividing resistor connected to the feedback pin.

[0007] A control module, including a PWM output port and a voltage acquisition port. The PWM output port is used to output PWM waves with different duty cycles to adjust the resistance value of the voltage-dividing resistor; the voltage acquisition port is used to acquire the voltage fed back by the device to be charged to determine the charging state of the device to be charged.

[0008] In some embodiments, the voltage-dividing resistor includes a first voltage-dividing resistor and a second voltage-dividing resistor;

[0009] The first end of the first voltage-dividing resistor is connected to the power output pin, and the second end of the first voltage-dividing resistor is connected to the feedback pin;

[0010] The first end of the second voltage-dividing resistor is connected to the feedback pin, and the second end of the second voltage-dividing resistor is grounded;

[0011] Wherein, the PWM output port is used to output PWM waves with different duty cycles to adjust the resistance value of the second voltage-dividing resistor to adjust the voltage output by the power output pin.

[0012] In some embodiments, the second voltage-dividing resistor includes a first resistor, a second resistor, and a MOS transistor;

[0013] The first end of the first resistor is connected to the feedback pin, and the second end of the first resistor is grounded;

[0014] The first end of the second resistor is connected to the feedback pin, the second end of the second resistor is connected to the drain of the MOS transistor, the source of the MOS transistor is grounded, and the gate of the MOS transistor is connected to the PWM output port.

[0015] In some embodiments, the second voltage-dividing resistor further includes a third resistor and a capacitor;

[0016] The third resistor is connected in series with the second resistor, the first end of the capacitor is connected between the second resistor and the third resistor, and the second end of the capacitor is grounded.

[0017] In some embodiments, the charging circuit further includes a pull-up resistor, the first end of the pull-up resistor is connected to the power output pin, and the second end of the pull-up resistor is connected to the drain.

[0018] In some embodiments, the charging circuit further includes a driving resistor, the first end of the driving resistor is connected to the gate, and the second end of the driving resistor is connected to the source.

[0019] In some embodiments, the charging circuit further includes a voltage feedback resistor, and the voltage fed back by the device to be charged is the voltage across the voltage feedback resistor;

[0020] The first end of the voltage feedback resistor is connected to the voltage acquisition port, and the second end of the voltage feedback resistor is grounded.

[0021] According to a second aspect of the embodiments of the present disclosure, there is provided an electronic device including a linear charging module;

[0022] The linear charging module includes a first charging terminal and a second charging terminal;

[0023] When charging the electronic device with the charging circuit based on the first aspect, the first charging terminal is electrically connected to the power output pin, and the second charging terminal is electrically connected to the voltage acquisition port.

[0024] According to a third aspect of the embodiments of the present disclosure, there is provided a charging method applied to the charging circuit as in the first aspect, including:

[0025] Determining the charging state of the device to be charged according to the voltage fed back by the device to be charged;

[0026] When the device to be charged is in the constant current charging state, adjusting the duty cycle of the PWM wave according to the voltage fed back by the device to be charged so as to adjust the voltage output from the power output pin.

[0027] In some embodiments, determining the charging state of the device to be charged according to the voltage fed back by the device to be charged includes:

[0028] When it is detected that the voltage fed back by the device to be charged reaches the preset voltage value, it is determined that the device to be charged is in the constant current charging state until the charging of the device to be charged ends.

[0029] In some embodiments, according to the voltage fed back by the device to be charged, adjusting the duty cycle of the PWM wave includes:

[0030] If the voltage fed back by the device to be charged is greater than the preset voltage value, then reduce the duty cycle of the PWM wave so as to reduce the voltage output by the power output pin.

[0031] In some embodiments, according to the voltage fed back by the device to be charged, adjusting the duty cycle of the PWM wave includes:

[0032] If the voltage fed back by the device to be charged is less than the preset voltage value, then increase the duty cycle of the PWM wave so as to increase the voltage output by the power output pin.

[0033] The technical solutions provided by the embodiments of the present disclosure may include the following beneficial effects:

[0034] The charging circuit provided by the embodiments of the present disclosure includes a boost module and a control module. Among them, the feedback pin in the boost module can adjust the voltage output by the power output pin according to the resistance value of the voltage dividing resistor connected to the feedback pin. The control module can output PWM waves with different duty cycles through the PWM output port so as to adjust the resistance value of the voltage dividing resistor, thereby achieving the purpose of adjusting the voltage output by the power output pin. In addition, the control module further includes a voltage acquisition port for determining the charging state of the device to be charged. Thus, the embodiments of the present disclosure can adjust the duty cycle of the PWM wave according to the charging state of the device to be charged, thereby flexibly adjusting the voltage output by the power output pin. The solutions of the embodiments of the present disclosure can improve the charging efficiency of the device to be charged, avoid energy loss, and at the same time reduce the heat generation of the device during the charging process.

[0035] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The circuit schematic diagram of a charging circuit in the embodiments of the present disclosure is shown.

[0037] Figure 2 The circuit schematic diagram of an electronic device in the embodiments of the present disclosure is shown.

[0038] Figure 3 The flowchart of a charging method in the embodiments of the present disclosure is shown.

[0039] Figure 4The figure shows a schematic flowchart of a TWS headset charging method according to an embodiment of the present disclosure.

[0040] Reference numerals:

[0041] 100 - charging circuit; 110 - boost module; 111 - first voltage - dividing resistor; 112 - second voltage - dividing resistor; 1121 - first resistor; 1122 - second resistor; 1123 - MOS transistor; 1124 - third resistor; 1125 - capacitor; 120 - control module; 130 - pull - up resistor; 140 - driving resistor; 150 - voltage feedback resistor; 160 - power supply module; 200 - electronic device; 210 - linear charging module; 211 - first charging terminal; 212 - second charging terminal; 220 - battery. Detailed implementation manners

[0042] Here, the exemplary embodiments will be described in detail, and the examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the present disclosure. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0043] The terms used in the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The singular forms "a", "the", and "said" used in the present disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0044] In addition, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0045] In the related art, the charging circuit usually outputs a stable and unchangeable constant voltage. However, current electronic devices usually adopt a linear charging method to improve the charging speed. Since the voltage requirements of linear charging are different in different stages, when the required voltage is less than the voltage output by the charging circuit, it will cause relatively high energy loss, resulting in low charging efficiency of the electronic device and an increase in the heat generated during the charging process of the electronic device.

[0046] In view of this, embodiments of the present disclosure provide a charging circuit, including a boost module and a control module. Among them, the feedback pin in the boost module can adjust the voltage output by the power output pin according to the resistance value of the voltage dividing resistor connected to the feedback pin. The control module can output PWM waves with different duty cycles through the PWM output port, so as to adjust the resistance value of the voltage dividing resistor, thereby achieving the purpose of adjusting the voltage output by the power output pin. In addition, the control module further includes a voltage acquisition port for determining the charging state of the device to be charged. The charging circuit provided by the embodiments of the present disclosure can adjust the duty cycle of the PWM wave according to the charging state of the device to be charged, thereby flexibly adjusting the voltage output by the power output pin, avoiding energy loss, and reducing the heat generation of the device during the charging process.

[0047] Next, the exemplary embodiments of the present disclosure will be described in detail.

[0048] Figure 1 The circuit schematic diagram of a charging circuit in an embodiment of the present disclosure is shown as Figure 1 As shown, the charging circuit 100 provided by the embodiments of the present disclosure includes a boost module 110 and a control module 120.

[0049] Among them, the boost module 110 can adopt any type of boost chip, and the control module 120 can adopt any type of microcontroller unit (MCU). The embodiments of the present disclosure will not elaborate on this.

[0050] It should be noted that the boost module 110 may include a power output pin Vout and a feedback pin FB. The power output pin Vout is connected to the first output terminal for charging the device to be charged. The feedback pin FB is used to adjust the voltage output by the power output pin Vout according to the resistance value of the voltage dividing resistor connected to the feedback pin.

[0051] The control module 120 may include a pulse width modulation (PWM) output port and a voltage acquisition port. Among them, the PWM output port is used to output PWM waves with different duty cycles, so as to adjust the resistance value of the voltage dividing resistor. The voltage acquisition port is used to collect the voltage fed back by the device to be charged, so as to determine the charging state of the device to be charged.

[0052] Among them, the duty cycle refers to the proportion of the high level in the PWM wave, that is, the proportion of the time of the high level in the total period. The voltage acquisition port may be the analog-to-digital converter (ADC) port of the MCU. The ADC port can detect the magnitude of the current returned by the device to be charged during the charging process, and then convert it into a voltage value according to the resistor connected to the ADC port.

[0053] Exemplarily, the charging circuit 100 further includes a voltage feedback resistor 150. The voltage fed back by the device to be charged can be the voltage across the voltage feedback resistor 150. The first end of the voltage feedback resistor 150 is connected to the voltage acquisition port, and the second end of the voltage feedback resistor 150 is grounded. When the charging circuit 100 charges the device to be charged, the voltage acquisition port can be connected to the charging terminal of the device to be charged. At this time, the current returned by the device to be charged will pass through the voltage feedback resistor 150. The voltage acquisition port can acquire the current returned by the device to be charged and convert it into a voltage according to the resistance value of the voltage feedback resistor 150.

[0054] Exemplarily, the charging state of the device to be charged can be determined according to the voltage fed back by the device to be charged. For example, when the voltage fed back by the device to be charged is not detected, it can be considered that the device to be charged is not in the charging state. When the voltage fed back by the device to be charged is detected to be greater than the preset voltage value, it can be considered that the voltage output by the power output pin Vout is greater than the voltage required by the device to be charged. At this time, unnecessary energy loss will occur, and the output voltage should be reduced. When the voltage fed back by the device to be charged is detected to be less than the preset voltage value, it can be considered that the voltage output by the power output pin Vout is less than the voltage required by the device to be charged. At this time, the output voltage can be increased to improve the charging speed of the device to be charged.

[0055] In some embodiments, the voltage dividing resistor includes a first voltage dividing resistor 111 and a second voltage dividing resistor 112. Among them, the first end of the first voltage dividing resistor 111 is connected to the power output pin, and the second end of the first voltage dividing resistor 111 is connected to the feedback pin. The first end of the second voltage dividing resistor 112 is connected to the feedback pin, and the second end of the second voltage dividing resistor 112 is grounded.

[0056] Exemplarily, the second voltage dividing resistor 112 can be a variable resistor. The equivalent resistance value of the second voltage dividing resistor 112 is determined by the duty cycle of the PWM wave output by the PWM output port. When the voltage output by the feedback pin FB is constant, the higher the duty cycle of the PWM wave, the lower the equivalent resistance value of the second voltage dividing resistor 112, and the higher the voltage output by the power output pin Vout. That is to say, by controlling the PWM wave with different duty cycles output by the PWM output port, the resistance value of the second voltage dividing resistor 112 can be adjusted, and then the voltage output by the power output pin can be adjusted.

[0057] Exemplarily, the second voltage dividing resistor 112 may include a first resistor 1121, a second resistor 1122, and a MOS transistor 1123. Among them, the first end of the first resistor 1121 is connected to the feedback pin, and the second end of the first resistor 1121 is grounded. The first end of the second resistor 1122 is connected to the feedback pin, and the second end of the second resistor 1122 is connected to the drain of the MOS transistor 1123. The source of the MOS transistor 1123 is grounded, and the gate of the MOS transistor 1123 is connected to the PWM output port for receiving the PWM wave output by the PWM output port, thereby controlling the on-off between the drain and the source. When the PWM output port outputs a high-level PWM wave, the drain and the source of the MOS transistor 1123 are turned on. At this time, the first resistor 1121 and the second resistor 1122 are in parallel, and the equivalent resistance value of the second voltage dividing resistor 112 is the resistance value of the first resistor 1121. When the PWM output port outputs a low-level PWM wave, the drain and the source of the MOS transistor 1123 are cut off, and the equivalent resistance value of the second voltage dividing resistor 112 is the resistance value of the first resistor 1121.

[0058] It should be noted that since the resistance value of the resistors in parallel will decrease, and when the equivalent resistance value of the second voltage dividing resistor 112 is too small, it will cause the voltage output by the power output pin Vout to be too large, resulting in damage to the device to be charged. Therefore, regarding the selection of the resistance value of the second resistor 1122, it should be ensured that when the second resistor 1122 is in parallel with the first resistor 1121, the voltage output by the power output pin Vout after being adjusted by the feedback pin FB is within a safe range.

[0059] Exemplarily, the second voltage dividing resistor 112 further includes a third resistor 1124 and a capacitor 1125. Among them, the third resistor 1124 is connected in series with the second resistor 1122, the first end of the capacitor 1125 is connected between the second resistor 1122 and the third resistor 1124, and the second end of the capacitor 1125 is grounded. It should be understood that the second resistor 1122 and the capacitor 1125 can form an RC filter. Since the PWM wave is a sawtooth waveform control signal, converting the sawtooth wave into a smooth wave through the RC filter can improve the stability and smoothness of the adjustment of the second voltage dividing resistor 112, thereby improving the stability of the voltage output by the power output pin Vout. The third resistor 1124 can prevent the two ends of the capacitor 1125 from being short-circuited when the MOS transistor 1123 is turned on, resulting in capacitor failure.

[0060] When the second voltage dividing resistor 112 includes a first resistor 1121, a second resistor 1122, a third resistor 1124, a MOS transistor 1123, and a capacitor 1125, when the drain and source of the MOS transistor 1123 are conducting, the second resistor 1122 and the third resistor 1124 are in series, and the first resistor 1121 is in parallel with the series-connected second resistor 1122 and third resistor 1124. At this time, the equivalent resistance value of the second resistor 1122 is the resistance value of the equivalent resistor composed of the above three resistors. When the drain and source of the MOS transistor 1123 are cut off, the equivalent resistance value of the second voltage dividing resistor 112 is still the resistance value of the first resistor 1121.

[0061] Exemplarily, when the second voltage dividing resistor 112 includes a first resistor 1121, a second resistor 1122, a third resistor 1124, a MOS transistor 1123, and a capacitor 1125, the voltage output by the power supply output pin Vout can be calculated in the following manner.

[0062] Specifically, when the drain and source of the MOS transistor 1123 are conducting, the voltage output by the power supply output pin Vout can be calculated by the following formula (1).

[0063]

[0064] When the drain and source of the MOS transistor 1123 are cut off, the voltage output by the power supply output pin Vout can be calculated by the following formula (2).

[0065]

[0066] In the above formula (1) and formula (2), V out is the voltage output by the power supply output pin Vout, V FB is the voltage output by the feedback pin FB, R 1 , R 2 , R 3 are the resistance values of the first resistor 1121, the second resistor 1122, and the third resistor 1124 respectively, and R A is the resistance value of the first voltage dividing resistor 111.

[0067] Exemplarily, the feedback pin FB can output a constant voltage. By adjusting the equivalent resistance value of the second voltage dividing resistor 112, the voltage output by the power supply output pin Vout can be adjusted, so that the charging circuit 100 can output a variable voltage.

[0068] It can be understood that by controlling the duty cycle of the PWM wave output by the PWM output port, the on-off cycle of the MOS transistor 1123 can be changed, and then the equivalent resistance value of the second voltage dividing resistor 112 can be changed periodically, so that the voltage output by the power output pin Vout can be smoothly adjusted between V calculated by the above formulas (1) and (2). out and

[0069] In some embodiments, the charging circuit 100 further includes a pull-up resistor 130. The first end of the pull-up resistor 130 is connected to the power output pin, and the second end of the pull-up resistor 130 is connected to the drain of the MOS transistor 1123.

[0070] In some embodiments, the charging circuit 100 further includes a driving resistor 140. The first end of the driving resistor 140 is connected to the gate, and the second end of the driving resistor 140 is connected to the source of the MOS transistor 1123.

[0071] By providing the corresponding pull-up resistor 130 and driving resistor 140 for the MOS transistor 1123, the on-off sensitivity of the MOS transistor 1123 can be improved, thereby improving the sensitivity to voltage control.

[0072] In some embodiments, the boost module 110 further includes an enable control pin EN. The control module 120 is connected to the enable control pin EN of the boost module 110, and can issue a control instruction to the enable control pin EN to control whether the power output pin Vout outputs voltage.

[0073] Exemplarily, when using the charging circuit 100 to charge the device to be charged, the power output pin Vout can be controlled to output voltage. When the charging circuit 100 is not connected to the device to be charged or the device to be charged is fully charged, the power output pin Vout can be controlled not to output voltage externally.

[0074] In some embodiments, the charging circuit 100 further includes a power supply module 160. Among them, the power supply module 160 can be a constant power supply (BAT), and the constant power supply is respectively connected to the boost module 110 and the control module 120 to supply power to the boost module 110 and the control module 120.

[0075] Thus, the embodiments of the present disclosure can adjust the duty cycle of the PWM wave according to the charging state of the device to be charged, so as to flexibly adjust the voltage output by the power output pin Vout.

[0076] The above Figure 1 has described in detail the charging circuit provided by the embodiments of the present disclosure. Based on the same inventive concept, the present disclosure also provides an electronic device, and the electronic device can be charged by the charging circuit as Figure 1 shown. When usingFigure 1 When the charging circuit shown charges an electronic device, the device to be charged can be understood as the electronic device itself.

[0077] Figure 2 FIG. shows a circuit schematic diagram of an electronic device according to an embodiment of the present disclosure. The electronic device 200 can be charged by docking a charging terminal with a charging circuit. Exemplarily, the electronic device 200 can be a Bluetooth headset, a smartwatch, a smart bracelet, smart glasses, a mobile phone without a standard charging interface in some cases, a certain charging back clip, or other electronic devices 200 that can be charged by wire through a docking method.

[0078] Exemplarily, the electronic device 200 includes a linear charging module 210. Among them, the linear charging module 210 is connected to the battery 220 in the electronic device 200, and is configured to receive the current output by a charging device and perform linear charging on the battery 220 in the electronic device 200.

[0079] Specifically, the linear charging module 210 includes a first charging terminal 211 and a second charging terminal 212. When charging the electronic device 200 based on Figure 1 the charging circuit shown, the first charging terminal 211 is conducted with the power output pin Vout, and the second charging terminal 212 is conducted with the voltage acquisition port.

[0080] Exemplarily, the second charging terminal 212 is also connected to the ground wire. When the charging circuit charges the electronic device 200, the current output by the charging circuit flows in through the first charging terminal 211 and returns to the charging circuit through the second charging terminal 212, thereby forming a charging loop.

[0081] It can be understood that since the current returning through the second charging terminal 212 passes through the above voltage feedback resistor, the voltage acquisition port can collect the voltage fed back by the electronic device 200 by detecting the magnitude of the returning current, so that the charging circuit can adjust the duty cycle of the PWM wave according to the collected voltage, thereby dynamically adjusting the voltage output from the power output pin Vout to the linear charging module 210.

[0082] Thus, the solution of the embodiment of the present disclosure can improve the charging efficiency of the electronic device, avoid energy loss, and at the same time reduce the heat generation of the electronic device during the charging process.

[0083] The present disclosure also provides a charging method. Specifically, Figure 3 FIG. shows a flowchart of a charging method according to an embodiment of the present disclosure. This method is applied to a charging circuit as Figure 1 shown. As Figure 3 shown, this method includes the following steps.

[0084] S301. Determine the charging state of the device to be charged according to the voltage fed back by the device to be charged.

[0085] It can be understood that when linearly charging the device to be charged using a charging circuit, the voltage fed back by the device to be charged can be detected in real time to determine the charging state of the device to be charged in real time. Exemplarily, when it is detected that the voltage fed back by the device to be charged reaches a preset voltage value, it can be determined that the device to be charged is in a constant current charging state until the charging of the device to be charged ends.

[0086] S302. When the device to be charged is in a constant current charging state, adjust the duty cycle of the PWM wave according to the voltage fed back by the device to be charged, so as to adjust the voltage output by the power output pin.

[0087] Exemplarily, if the voltage fed back by the device to be charged is greater than the preset voltage value, the duty cycle of the PWM wave can be reduced to reduce the voltage output by the power output pin Vout. If the voltage fed back by the device to be charged is less than the preset voltage value, the duty cycle of the PWM wave can be increased to increase the voltage output by the power output pin Vout. And if the voltage fed back by the device to be charged is equal to the preset voltage value, the current duty cycle of the PWM wave is maintained to keep the voltage currently output by the power output pin Vout.

[0088] It should be noted that the above preset voltage value can be calibrated through experiments. It can be understood that in the constant current charging state, when the voltage fed back by the device to be charged is greater than the preset voltage value, the voltage output by the charging circuit is greater than the voltage required by the device to be charged. At this time, the duty cycle of the PWM wave can be reduced to reduce the voltage output by the charging circuit to avoid energy loss and at the same time reduce the temperature of the device to be charged during charging. And when the voltage fed back by the device to be charged is less than the preset voltage value, the voltage output by the charging circuit is less than the voltage required by the device to be charged. At this time, the duty cycle of the PWM wave can be increased to increase the voltage output by the charging circuit so that the device to be charged can be charged more quickly.

[0089] Exemplarily, when the increased duty cycle of the PWM wave reaches 100, the duty cycle of the PWM wave can be maintained at 100 until the charging of the device to be charged ends, so that the device to be charged is maintained in a fast charging state.

[0090] The following will combine specific application scenarios to Figure 3 describe the charging method shown in detail.

[0091] Exemplarily, Figure 4The figure shows a schematic flowchart of a method for charging a TWS headset in an embodiment of the present disclosure. Among them, a true wireless stereo (TWS) headset includes a headset body and a headset charging case. A charging circuit as shown in Figure 1 may be configured in the headset charging case to charge the headset body.

[0092] Specifically, the method includes the following steps.

[0093] S401, Detect whether the headset body is placed in the headset charging case.

[0094] Exemplarily, the headset body can be understood as Figure 2 the electronic device shown. When the headset body is placed in the headset charging case, the first charging terminal on the headset body is conducted with the power output pin Vout in the headset charging case, and the second charging terminal on the headset body is conducted with the voltage acquisition port in the headset charging case.

[0095] At this time, if the voltage acquired by the voltage acquisition port is the voltage fed back during the charging of the headset body, it is considered that the headset body has been placed in the headset charging case.

[0096] S402, The PWM output port outputs a constant high waveform.

[0097] S403, Detect whether the voltage fed back during the charging of the headset body is less than a preset voltage value.

[0098] If so, jump to S404; if not, jump to S405.

[0099] Exemplarily, the preset voltage value can be based on the reference voltage calibrated through experiments, and the embodiments of the present disclosure will not elaborate on this.

[0100] S404, Keep the PWM output port outputting a constant high waveform, and return to S403 to continue detecting the voltage fed back during the charging of the headset body.

[0101] S405, Determine that the headset body is in a constant current charging state.

[0102] S406, Reduce the duty cycle of the PWM wave to reduce the Vout output voltage.

[0103] Exemplarily, by reducing the duty cycle of the PWM wave output by the control module in the headset charging case, the voltage output by the power output pin Vout in the headset case can be reduced to avoid energy loss caused by excessive voltage.

[0104] S407, Compare the voltage fed back during the charging of the headset body with the preset voltage value.

[0105] If the voltage fed back during the charging of the headset body is greater than the preset voltage value, return to S406.

[0106] If the voltage fed back during the charging of the earphone body is less than the preset voltage value, then jump to S408.

[0107] If the voltage fed back during the charging of the earphone body is equal to the preset voltage value, then jump to S409.

[0108] S408, maintain the current duty cycle of the PWM wave to maintain the Vout output voltage, and return to S407 to continue detecting the voltage fed back during the charging of the earphone body.

[0109] S409, increase the duty cycle of the PWM wave to increase the Vout output voltage.

[0110] Exemplarily, by increasing the duty cycle of the PWM wave output by the control module in the earphone charging case, the voltage output from the power output pin Vout in the earphone case can be increased to ensure the charging speed of the earphone body.

[0111] S410, detect whether the duty cycle of the PWM wave reaches 100.

[0112] If so, then continue to execute S411.

[0113] If not, then return to S407 to continue detecting the voltage fed back during the charging of the earphone body.

[0114] S411, maintain the current duty cycle of the PWM wave until the charging of the earphone body ends.

[0115] Thus, the TWS earphone charging method provided by the embodiments of the present disclosure can flexibly adjust the charging voltage of the TWS earphone in the constant current stage, thereby avoiding energy loss caused by too high a voltage and avoiding excessive heat generation during the charging of the TWS earphone.

[0116] The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0117] In addition, it should be noted that, in the above specific embodiments, the various specific technical features described can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present disclosure does not separately describe various possible combination methods.

[0118] Furthermore, any combination can be made between various different embodiments of the present disclosure as long as it does not violate the idea of the present disclosure, and it should also be regarded as the content disclosed by the present disclosure.

Claims

1. A charging circuit, characterized in that, it includes: A boost module, including a power output pin and a feedback pin, the power output pin is used to charge the device to be charged; the feedback pin is used to adjust the voltage output by the power output pin according to the resistance value of the voltage dividing resistor connected to the feedback pin; A control module, including a PWM output port and a voltage acquisition port, the PWM output port is used to output PWM waves with different duty cycles to adjust the resistance value of the voltage dividing resistor; The voltage acquisition port is used to acquire the voltage fed back by the device to be charged to determine the charging state of the device to be charged.

2. The charging circuit according to claim 1, characterized in that, the voltage dividing resistor includes a first voltage dividing resistor and a second voltage dividing resistor; The first end of the first voltage dividing resistor is connected to the power output pin, and the second end of the first voltage dividing resistor is connected to the feedback pin; The first end of the second voltage dividing resistor is connected to the feedback pin, and the second end of the second voltage dividing resistor is grounded; Wherein, the PWM output port is used to output PWM waves with different duty cycles to adjust the resistance value of the second voltage dividing resistor to adjust the voltage output by the power output pin.

3. The charging circuit according to claim 2, characterized in that, the second voltage dividing resistor includes a first resistor, a second resistor and a MOS transistor; The first end of the first resistor is connected to the feedback pin, and the second end of the first resistor is grounded; The first end of the second resistor is connected to the feedback pin, the second end of the second resistor is connected to the drain of the MOS transistor, the source of the MOS transistor is grounded, and the gate of the MOS transistor is connected to the PWM output port.

4. The charging circuit according to claim 3, characterized in that, the second voltage dividing resistor further includes a third resistor and a capacitor; The third resistor is connected in series with the second resistor, the first end of the capacitor is connected between the second resistor and the third resistor, and the second end of the capacitor is grounded.

5. The charging circuit according to claim 3, characterized in that, the charging circuit further includes a pull-up resistor, the first end of the pull-up resistor is connected to the power output pin, and the second end of the pull-up resistor is connected to the drain.

6. The charging circuit according to claim 3, characterized in that, the charging circuit further includes a driving resistor, the first end of the driving resistor is connected to the gate, and the second end of the driving resistor is connected to the source.

7. The charging circuit according to claim 1, characterized in that, the charging circuit further includes a voltage feedback resistor, and the voltage fed back by the device to be charged is the voltage on the voltage feedback resistor; The first end of the voltage feedback resistor is connected to the voltage acquisition port, and the second end of the voltage feedback resistor is grounded.

8. An electronic device, characterized in that, it includes a linear charging module; The linear charging module includes a first charging terminal and a second charging terminal; When charging the electronic device based on the charging circuit according to any one of claims 1 to 7, the first charging terminal is electrically connected to the power output pin, and the second charging terminal is electrically connected to the voltage acquisition port.

9. A charging method, characterized in that, applied to the charging circuit according to any one of claims 1 to 7, comprising: determining the charging state of the device to be charged according to the voltage fed back by the device to be charged; when the device to be charged is in the constant current charging state, adjusting the duty cycle of the PWM wave according to the voltage fed back by the device to be charged, so as to adjust the voltage output by the power output pin.

10. The method according to claim 9, characterized in that, the determining the charging state of the device to be charged according to the voltage fed back by the device to be charged comprises: when it is detected that the voltage fed back by the device to be charged reaches a preset voltage value, determining that the device to be charged is in the constant current charging state until the charging of the device to be charged ends.

11. The method according to claim 9, characterized in that, the adjusting the duty cycle of the PWM wave according to the voltage fed back by the device to be charged comprises: if the voltage fed back by the device to be charged is greater than the preset voltage value, reducing the duty cycle of the PWM wave so as to reduce the voltage output by the power output pin.

12. The method according to claim 9, characterized in that, the adjusting the duty cycle of the PWM wave according to the voltage fed back by the device to be charged comprises: if the voltage fed back by the device to be charged is less than the preset voltage value, increasing the duty cycle of the PWM wave so as to increase the voltage output by the power output pin.

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